Dental tray



1 Dec. 21 1926.

W. N. KIDDER DENTAL TRAY 7 Filed July 13, 1923 t of the'jaw. o

Patented Dec. 21, 1926.

- emetstares WILLIAM 1v. KIDDEB, or'nununn, RHO E ISLAND.

DENTAL TRAY;

' Application filed July 13,

This invention relates to improvements in the construction of. clentalimpression trays, and has for its object to provide a tray of this character having its body shaped'to take I a full-jaw impression and also having the front portion of the body removable, Whereby the tray may be readily removed from the jaw after having taken an impression thereof. i

1 A further object of this invention is the provision of an inturned cleavage ridge on the line of separation between the front sec- 'tion' and the body portion. I

The invention further conslsts in the prof vision of 'a separate, separable, 'cooperating impression unit or;cup adapted to be first applied to take the impression of a selected tooth or group of teeth which-may be malformed or mal-po'sed and. after the impres- 29 sion material thereinhas hardenedthe main my carrying its impression material is inserted into the mouth and the unit withithe rest of the jaw is impressedthereinto With theseand other objects in View, the

invention consists of certain novel features of construction, as will be more fully; de-

scribed, and particularly pointed out in the appended claims. w r

In the accompanying drawings :e-

39 Figure 1 is a plan view showing my improved tray with the removable front section connected thereto.

Figure2 is thesame as ing a pair of individual impression units as 3 being inserted into opposite sides of the tray forthe purpose "of taking a separate im- Figure 1,?but showpression of a selected tooth' orgroup of 'malformed or "mal-posed teeth' simultaneously with the taking of an impression oflthe rest.

Figure 3 is a'perspective view showing the body portion of my improved dental impression tray with the front section removed.

Figure lis a perspective view of the'front section removed from the body portion of thetray. v v or I .7 V F1gure'5 is a sectionalele'vation online 5 5 of Figure 4, ofthe frontremovable section Figurefi is a section'onli'ne -6--6 of Figeas. serau No. 651,226.: g r v I ure 3, through the body portion ofthe tray. Figure 7 is aperspective view showing one half of one oftlie' separate impression units.

Figure 8 1s a central section through the I dental impression unit, takenon linefl8 8 'to provide this section with a fracture rib, or

ridge along its line of separation to facilitate theifracturing of the impression 'material to permit removal of the body of the tray 7 from the jaw after having taken'a'n impressionofthemouth. 7 It is also found of advantage to so; shape the tray that it is adapted to receiv'e independent impression units which are employed for taking a separate impression of the posterior teeth" independently of. the 'taking of an impression of the rest ofthe jaw,

is in-the main portion of the tray whereby an accurate impression of mal-p'osed or fmal formedteeth, is obtained, and after the'im p'ression' materialutherein has hardened the 8 main tray carrying its impression material is inserted into the mouth and the unit with the 'rest of thejaw is impressed thereinto; The tray body is then removed and subsequently the unitis splitsand removedfromthe tootlland replaced in its molded socket inthe tray to complete the full impression in the tray."

The following is a detailed, description of v such a dental impression tray by which these l advantageous results may be accomplished:

i With reference to the drawings, 10 desig-.

nates the body portion of my im'proved 'sectional dental impression tray, which? is 'formedin channel or trough shape havingouter edge wallsll and i-nneredge walls'12, 9

the channel being preferably open as at 13 on its inner ends forming channel-shaped 6X tensions adapted to take an impression of the posterior portion of the month including 7 guide tongue 17 of the removable-section ISI This section is provided with an outer wall portion 19 which when in position serves to make 'acontinuous outer wall about thebody portion. This removable section is also providedwith a bottom plate 20 which is a continuation ofthe bottom plate 21 of the mainbody portion, and the meeting edge of this removable section is turned upwardly as at 22 forming a sharp fracture ridge in this section, whichis adapted to cause the plaster of this'mold-to crack along the line of this fracture ridge'so that when it is desired to remove this section; this portion of the plaster willbe removed therewith, thereby removing the front portion of the mold from the-teeth permittingthe main body portion of thetray tobe much more readilyremoved from the'rear or posterior portion of the mouth; v v This removable section is also provided with an operating handle 23 which is adapted when in position, to lie in alignment with the'han dle 14 of themain tray and V rest thereupon for the purpose of supporting this removable section andpermitting it to be operated in connection with the body portion upon being positioned in the mouth ofthe patient. i

' It is foundin some instances, where the jaw and interdentulous spaces and mal-posed and mal formed teeth, ofadvantage in order toobtain a correct impression of such teeth, to provide separate and indepen'dentmoldunits for such teeth. These independent molding units 24. being preferably formed cup-shaped as best illustrated in Figures 7 and 8, an-d are separable along their center lineas at 2 5 and are provided-with inturned fracture ridges 26 along their meeting edges,

the same being preferably formed of lead or other soft materials, permitting their edges tobe cut and shaped to fit-the gum o-fthepatient, the closed ends 27 of these cups being so shaped that'they are adapted to set intoth-e impressionfinaterial in the rear of the trough-shaped portion a of the body member of thetray. These molding units may be set into the body of the tray and be,fthem selves, filled with impression material, whereby these independent molding units are adapted to take an impression of such unusual teeth and at the same time that the impression of the rest of the jaw is being taken in the body of the tray. After the whole impression is taken the front removable section is first withdrawn to obtain a correct impression of the front or labial surface of the anterior teeth and to permit a free removal of the body of the tray from the rear, portion of the jaw; next the body portionof the tray is removed leaving the independent mold units still connected to the posterior teeth; next these individual molds or units are split apart by the LlSQ'Of a wedging instrument, their fracture ridges serving to split the plaster or impression material on the desiredline, to permit ofits ready removal. These units are thenlagain reassembledf and repositioned in their depressions in the pression material in the main body of'the tray; then the front sectionis again positionedonthe body portion and'the-whole is then ready to receive the molding material which is poured thereinto, whereby an absolutely correct reproduction of the-teeth and interdentulous spaces. is obtained, together with that of the mal-posed or mal-formed teeth which. were obtainedinthe. individual molds. T

' The foregoing description is directed solely towards the'construotion illustrated but I desire it to be understood that I reserve the privilege of resorting to all. the mechanical changes to which the deviceissusceptible, the invention-being defined and limitedionly by the terms of the appendedf'claims.

I claim: 7 t I 1. A dental impression tray comprising a channeled body portion shaped to carryimpression compound and take a full jaw'impression, and having an independentfront section adapted tobe positioned on saidbody portion .tocomplete the front portion thereof for taking the impression, said section being readily removable to be separatedand takenfrom the body with that portion of the compound carried by it after the impression has been taken. y

2. A dental impression 1 tray having "a channeled bodyportion. shaped to carryiimpression compound and take a full jaw imreadily separated and removed therefrom and having a cleavage ridge on the l ne of SQJLOELPQUOII, whereby it may be removed with that portion of the compound carried by it cleavage ridge on the line of separation, and

guiding means to assist in re-po-sitioning sald section after having been removed from the body portion. 1

rec

pression, an independent "front section 1.1

adapted to be positioned on said body to be 5 said front Wall and a portion of the bottom Wall being removably mounted. on said body, whereby itmay be separated and taken from said body.

5. A- dental impression tray having a 10 channeled body portion shaped to take a full-jaw impression, a front section carry-.

ing the front Wall, and a portion of the bot tom Wall removably mounted on said body and having a cleavage bottom ridgeon the line of separation, an operating handle on said body, and a cooperating handle on mid section whereby said section and body may be manipulated either collectively or sep arately. In testimony whereof I afiix' my signature,

WILLIAM N. KIDDER. 

